Questions on IQ's of ethnic groups
Mr. Sloan,

Thank you for your response.  After reading through your comments I am even less convinced that your selection of information and the conclusions you have drawn from it point to any correlation between race and IQ.

Firstly, it seems you present certain ideas as fact when they are still being questioned by equally qualified researchers on both sides of the race/intellect debate.  From what I can tell, this debate is fueled by research as opposed to political correctness.
Sloan replies:  In any field, there are varied opinions.  What I present in my website is the majority opinion of academic researchers.

Secondly, the information you present does not conclusively point to race as a determinant of IQ any more than it points to race as a determinant of whether someone will be born with a sense of humor, leadership ability or drafting skills.  In other words, it seems that intelligence, like personality, is more determined by factors both clear and mysterious such as your parents' choice of mate, environmental stimuli, fatty acids, breastfeeding, chance... 

Given that, I would be interested to hear your responses to the following questions:

1.  Your claim:  "Measures of intelligence like SAT tests show consistent group differences that are not explainable by culture or class"

     My questions: 

      - Where is the evidence that blacks and whites from the full spectrum of socioeconomic and cultural   
            backgrounds comprised the sample groups from which these conclusions were drawn?  In other words,
            who gets sampled and what are the selection criteria?
Sloan replies: The charts in show how various ethnic groups score on SAT tests.  It is noteworthy that Hispanic SAT scores are higher than those of Blacks, yet the incomes of the two groups are about the same.  Both groups have a higher percentage of high school dropouts than Whites.  So their SAT scores come from a smaller percent of their population than the scores for Whites.  If all high school students were tested for SAT or IQ, it is likely that average Hispanic and Black scores would be even lower than the White averages.   
        - Moreover, does said evidence take into account that that many success-minded upper class parents
            will pay princely sums for Kaplan courses in order to boost their kids' SAT scores?  I
            remember meeting several white students in college who took expensive courses to increase their
            previously lackluster test scores.  See also:
Sloan replies:  The data on Kaplan/ Princeton Review success in raising SAT scores has not been available publicly for academic scrutiny.  
      - If the SAT-based IQ figures you present are averages, how do you account for the high end of black
            test scores, or outliers, that contribute to the black average?  If blacks were mentally
            incapable of surpassing a Caucasian score, as your website implies, how do you explain the ones that
            do? I am certain that these black outliers exist as I have met some of them: a female African
            acquaintance with a summa cum laude from Yale Law School and magna cum laude from Harvard, a
            fraternal cousin and uncle with genius IQs...  If blacks are destined for lower intelligence no
            matter what mitigating factors come into their lives, then why do some blacks far exceed their white
            and Asian counterparts?
Sloan replies: Like all physical characteristics that occur in a bell curve distribution, IQ's of all ethnic groups include some very high (and very low) individual scores. 

     -  Similarly, how would you explain the significant difference in IQ scores amongst whites that belong
            to the same regions, ethnic groups and genetic stock?
Sloan replies:  Scientists do not have good data or analysis for all IQ questions. Where there is no clear majority opinion, I usually do not include such topics in my website.  There has been much analysis of the difference between the higher IQ's of Jews of Eastern European vs Jews of Mediterranean background.  Scientists generally feel that varying persecutions (like Holocaust) and survival rates are related to that IQ difference.
        The same radio program that I mentioned before, This American Life, has done a number of interesting
            shows that illuminate the nature of intelligence.  They did a show on two women who were switched at
            birth.  They were from similar ethnic stock and socioeconomic class. The women talked about
            their experiences unknowingly growing up in families that were not their own.  One woman described
            how she had a completely different personality and aptitude than her supposed siblings.  They,
            along with their biological parents were bookish, high achieving and conservative.  She was outgoing
            and a marginal student with none of their academic talent, although she seemed to have superior
            people skills.  If being of Germanic stock and good health ensures that you have a higher intellect
            than everyone else, then why was there a marked aptitude difference between these two women?  Surely
            other factors come into play when mental capacity is determined in the womb.
Sloan replies: Anecdotal evidence is not as strong as data.  And sibling differences are much greater that the genetics of identical twins. 

2.  Your claim (regarding twins raised by different families):  "Their different environments cause only a 10-20% difference in their IQ's".

     My question:

       - In upper class culture, many people choose a mate based on their intellectual prowess.  Many upper
             class families put outward pressure on their children to pick a mate that has gone to a good
             school, has a prestigious job, etc.  Conversely, in many lower class families selection of a mate
             may have more to do with criteria such as having a caring personality, being a breadwinner, being
             handsome or being humorous with high IQ having less weight in the decision.  In any case, when
             people of any class reproduce, they pass on their genes to their children.
             However, given the existence of IQ disparities among very similar whites and the existence of
             blacks and Africans that score higher than whites and Asians, one could rightfully conclude that
             race is not a determinant of intellect.  If anything, these disparities point toward choice of mate
             as a strong factor in determining the intellect of one's progeny.  What is your take on the issue?
Sloan replies: You make some assertions that choosing a mate varies  in different ethnic groups.  I find no data to confirm this.

2.  Your claim: "It is true that IQ tests require reading and other skills learned in the classroom.   But they mainly test for problem-solving abilities, not facts learned at school.  Most respected IQ-type tests (like the SAT-1) have been well researched for flaws and their scores have been shown to correlate well with each other."

    My questions:

          - There is no consensus that the SAT is an IQ test.  It seems that you are lumping together
            intelligence tests and standardized achievement tests when the two tests contain different content
            and measure different aptitudes.  From what I understand most IQ tests measure for pattern
            recognition, memory, logic, reasoning, spatial evaluation and other non-school related aptitudes,
            evidenced by the fact that many IQ tests are administered to small children. 
     SAT tests on the other hand are mainly achievement tests that measure one's ability to apply
            arithmetic principles to scenarios, one's memorization of vocabulary and word sense, reading
            comprehension and test-taking ability in addition to basic logic. 

        When I took the SAT in the early 90s I tested in the top percentile and I never took a course to
            help my chances.   When I took practice tests with no pressure I often aced the tests or had one or
            two mistakes that I could easily detect on a second pass.   Nonetheless, I know that my IQ would NOT
            have helped me do well on the SAT at all had I not had a rigorous and challenging formation in math
            and english.   

        Given that, how can you say that the SAT is an IQ test when the verbal part of the exam measures
            vocabulary level and reading comprehension?  Those are skills you hone in a well run English class
            that exposes you to British English through literature (a lot of the "harder" vocabulary words are
            found more often in written and spoken British English than in American English).   And clearly, you
            would not do well on the mathematical portion of the test had you not memorized and repeatedly
            applied algebraic/geometric formulas and theorems as part of your homework routine over
            many years.  Try taking an SAT test now and compare the results with the ones you received as a
            teenager still in school.  You'll probably see that your math abilities have atrophied independent
            of your level of intelligence.

            Admittedly, there are logic problems on the SAT but having a highly logical mind alone and no
            exposure to academic subjects will not win you a good score on the test.  Also, I think it is fair
            to say that being in challenging courses affords you a more agile mind that is better equipped to
            handle logic questions.

            Thus, is it fair to look at SAT averages as a measure of IQ?  To me they mainly seem like a measure
            of schooling and test-taking ability, with some reference to innate intelligence.
Sloan replies: Yes, the SAT is structured differently than some IQ tests.  But the important point is: "The SAT and IQ test correlate very highly. Between the SAT and the IQ, they correlate almost as much as the SAT correlates with a second administration of the SAT, as much as it correlates with itself." Quote by Stanford Psychology department chair.  This and similar quotes from respected academics at 

3. Your claim: "Early Childhood Education programs do give a boost to school performance of youngsters.  But the boost is only temporary." 

    My questions:

    -  Research shows that heritable and functional IQ fluctuate throughout one's lifespan and can be temporarily boosted by changes in one's environment.  This is true for all races.  Given that, wouldn't a program like Head Start fall into the category of a temporary change of environment?  Thus, wouldn't it follow that once it is taken away with all other factors remain the same that a child would be in danger of losing the temporary gains?  
Sloan replies: Head Start evidence supports the conclusions implied by your questions above, especially for temporary boosts in IQ scores. 

       So what is responsible for reversing the progress made by HeadStart?  I don't think it's racial inferiority; I think it's environment.  One thing you may not see is that many families of a working class culture do not cherish academic achievement in the same way upper class families do.  They tend not to put as much pressure on their kids to pursue mind-expanding extra curricular activities like studying a musical instrument or foreign language.  They talk about different things at the dinner table.  Expectations in lower class families may be set at a lower bar (i.e. a poor family with no college graduates may be ecstatic if one their own goes to a local college whereas a wealthy family will only be satisfied if their kid gets into an Ivy League school--after prepping him for it all his life.)  I don't know if your theories take into account the environment kids spend their time in out of school and how that can determine their abilities. 
Sloan replies: Nobody really knows the reasons for Head Start's lack of permanent gains in some school performance measures.

    - On your Educational Equality page you mention that blacks tend to perform better in Olympic running events because of their physical attributes and from that one can conclude that brain capacity must vary by race as well.  Following that logic I could say that white people, being deficient in melanin compared to        blacks, must somehow be deficient in their brain capacity compared to blacks.  Sounds silly right?  Frankly, your Olympics statement recalls Nazi thought and is a bit crypto-racist.  If anything, it makes your site seem like it is based on confirmation bias (i.e. I want to believe that whites are superior so I will construct      a case to defend that position).  How would you respond to that?   
Sloan replies:  The majority of Americans in all ethnic groups believe, as you do, that IQ group differences are caused by environmental factors.  The majority of researchers in the IQ field believe that the differences are caused mostly by genetic factors.  Occasionally there is some hard evidence of environmental impact, as I added to finding: 2005 research indicates that children's IQ scores improved 5 points after studying Chinese characters)
The difference between what is popularly believed and what researchers believe (on group IQ's) bothers me.  It leads to unrealistic expectations of what teachers and administrators in low income school districts ought to be able to achieve.

   3.  You claim: "Researchers also agree that IQ is set for life by age five or earlier" 

    My questions:

    - I have read several articles claiming otherwise.  Some say IQ increases through adolescence.  Others say that heritable IQ is is not static and that it can be enhanced by a number of different environmental factors.  Why have you chosen to reject what other researchers claim?   See:
Sloan replies:  The Flynn effect (of IQ's increasing worldwide over time) is real, but its causes are not understood.   On IQ changing during one's lifetime, the reality depends on the definition of IQ.  Yes, a child's ability to think through problems improves through adolescence, and it declines in old age, particularly in math skills.  But IQ is really a measure of an individual's intelligence relative to his peers of the same age.  Most evidence shows that relative intelligence (IQ) does not change after age 5. 

Awaiting your response,  (now in bold above) 


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